Highways account for some of the most important transport arteries connecting the various regions and urban conglomerations. The first highway, the D1 destined for Brno, began construction in May 1939, was halted in 1942, and recommenced in 1945. It is known for being made out of uneven slabs of concrete, which are guaranteed to massage you on your way to Brno. New full-scale reconstruction has begun in 2012. The Czech Republic has 6 highways currently in operation (D1, D2, D3, D5, D8 and D11), amounting to 726.9 kilometers of roads. In addition to this, there are 16 expressways known as rychlostní silnice, designated by the prefix “R” and totaling 391.2 km.